This invention relates generally to safety equipment for school busses and more particularly to a crossing arm assembly for mounting on the front end of a school bus. When the school bus stops the crossing arm assembly is extended to a perpendicular position to prevent departing passengers from crossing immediately in front of the school bus as shown in U.S. Pat. No. 5,357,239 granted to me Oct. 18, 1994. In my earlier patent the crossing arm assembly, also referred to as a safety gate, is shown as a solid bar that is attached to a metal bracket at one end for pivotally mounting the solid bar on a housing.
Attempts have been made to provide improved crossing arm arrangements. For instance, U.S. Pat. No. 4,697,541 granted to James H. Wicker Oct. 6, 1987 discloses a crossing arm unit that comprises a short pivot plate of a sturdy relatively heavy gage metal (e.g. 3.5 in. of 14 gauge steel), a longer support plate 32 of relatively light gage metal (e.g. 20 in. of 0.08 in. aluminum plate) and a long U-shaped rod (e.g. 4 ft. of 1/4 in. aluminum rod). According to the Wicker patent specification the crossing arm unit is light weight to avoid structural problems with its pivotal support, is easily supported, is simple in construction, and is economical to manufacture. The Wicker patent at column 1 also states that crossing arms have been made of light weight fiber glass rods and that his construction is an improvement over these prior art constructions.
The Wicker construction, however, is unduly complicated particularly when assembly is taken into account. Moreover, the long U-shaped rod is fragile, deforms easily and requires a strut that further complicates the construction and adds to the expense of the Wicker construction. Furthermore, the U-shaped rod which serves as the pedestrian barrier has low visibility.
U.S. Pat. No. 5,199,754 granted to Lowell J. D. Freeman discloses a crossing arm or barrier which is of tubular fiberglass construction. While the Freeman crossing arm is simple in construction in comparison to the Wicker construction, the Freeman single rod is also fragile and also has low visibility.
U.S. Pat. No. 3,153,398 granted to George LaVerne Runkle and Gilbert S. Sheets Oct. 20, 1964 discloses a crossing arm structure that comprises a channel shaped section of light sheet metal that is stiffened by a U-section having out-turned legs fixed to the back of the channel shaped section. The crossing arm assembly is shaped to fit in a recess in the front bumper and also includes a rubber guard structure that has a hollow rectangular center portion that is cemented to the channel section and flange portions that seal off the bumper recess.
This crossing arm structure of this arrangement is also unduly complicated and expensive to manufacture. Furthermore the arrangement requires a hinge structure for attaching the crossing arm to the bumper that further complicates the construction and adds to the expense.